Patrick said the "terrible tragedy" is a reminder to be grateful every day "for the brave men and women who put themselves in danger day in and day out to keep us safe."

New England Patriots quarterback Tom Brady, who lives in the Back Bay, said he extends "deepest sympathies and condolences" to the fire department and families "of our brave and selfless firefighters who gave their lives for our protection and safety today."

Boston Cardinal Sean O'Malley said he prays "for God's gift of peace for all impacted by this devastating loss."